A narrow strait splits Asian and Australian wildlife

Crossing the Lombok Strait between Bali and Lombok, naturalist Alfred Russel Wallace noticed the animals change abruptly: tigers, monkeys and woodpeckers to the west, cockatoos and marsupial relatives to the east. The deep-water channel stayed open even during ice-age sea-level drops that connected other nearby islands by land bridge, so species from each side never mixed. It's now called the Wallace Line in his honour.

— Alfred Russel Wallace, The Malay Archipelago — 1869
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